The present invention is directed to a valve assembly for use with a fluid filter, which valve assembly establishes a first fluid flow path to place the filter in the flow path of the fluid to be filtered and a second fluid flow path bypassing the filter to facilitate removal and replacement of the filter.
There are many instances wherein the taste and odor of household tap water can be improved by filtering certain impurities or minerals from the water. To that end, filters are known which contain a suitable filtering medium such as activated charcoal. Such filters usually take the form of replaceable filter cartridges which are tubular in configuration.
To facilitate removal of the filter cartridges, valve assemblies are known which establish selectable fluid flow paths for the water, one flow path including the filter cartridge, and another flow path bypassing the cartridge. The last-mentioned flow path allows the water to be used while affording the user with an opportunity to remove and replace the filter cartridge.
Water filter assemblies primarily take two different forms. One form is directly mountable to a water faucet. The other form may be employed in a water line upstream from the water faucet in an inconspicuous place, such as below a sink, or within the home main water line. Both forms may utilize the aforementioned valve assemblies which establish selectable paths for the water to facilitate the removal and replacement of the filter cartridges.
When the valve assemblies are placed into the filter bypassing mode, they have had a tendency to leak. Such leakage is not particularly serious in the case of a faucet mounted filter assembly because the leaking water merely drips into the sink. However, in the case of a filter assembly mounted below a sink, in a kitchen cabinet, for example, the leaking water may go undetected for an extended period of time and cause damage to the bottom panel of the cabinet.
It is therefore an object of the present invention to provide a new and improved water filter assembly which does not leak when placed into a filter bypass mode.
It is a more particular object of the present invention to provide an improved valve assembly of the type stated for use in such a filter arrangement which provides selectable fluid flow paths for the water and which does not leak when placed in a filter bypass mode.
The invention therefore provides a valve arrangement for use in a fluid filter assembly having a fluid filter. The valve arrangement comprises a housing adapted to retain the fluid filter and having an inlet adapted to be coupled to a source of fluid to be filtered, an outlet, and first and second bore means communicating with the inlet and outlet respectively, and a valve member within the housing which is movable with respect to the housing between first and second position for establishing a first fluid flow path between the inlet and the outlet which includes a fluid filter and a second fluid flow path between the inlet and the outlet which bypasses the fluid filter. The valve member includes first and second channels arranged for communicating with the fluid filter and arranged to communicate with the first and second bore means respectively when the valve member is at the first position for establishing the first fluid flow path which includes the fluid filter, a third channel arranged for direct fluid communication between the inlet and the outlet when the valve member is at the second position for establishing the second fluid flow path which bypasses the fluid filter, and seal means for sealing the first and second bore means when the valve member is at the second position. The seal means comprises first and second seal members arranged to engage the first and second bore means respectively and arranged to be held in fluid tight engagement with the bore means by a force created by the pressure of the fluid flowing between the inlet and the outlet. The seal member has a through aperture communicating the bore with the chamber to allow the fluid to enter and charge the chamber for forcing the seal member against the bore in tight fluid sealing engagement therewith.